Actuator having an adjustable auxiliary output

Abstract

An actuator system having an actuator with an auxiliary switch. Make and break connection positions of the auxiliary switch relative to a rotative position of an output shaft coupling may be adjusted electronically according to an adjustment signal. The adjustment signal may be conveyed to the actuator from a computer or controller via a two-wire polarity insensitive bus. The adjustment signal may instead be provided an auxiliary potentiometer.

What is claimed is: 
     
       1. An actuator system for a heating, ventilating and air conditioning (HVAC) system, comprising:
 a motor having an output; 
 a gear train having an input connected to the output of the motor and having an output shaft coupling for an HVAC actuator; 
 a shaft rotation position sensor proximate to the output shaft coupling; and 
 an auxiliary switch having a make-connection position and a break-connection position relative to a rotation position of the output shaft coupling; and 
 wherein:
 the make-connection position and the break-connection position are separately adjustable electronically relative to a rotation position of the output shaft coupling; and 
 the make-connection position and the break-connection position are separately adjustable electronically according an adjustment signal external to the actuator. 
 
 
     
     
       2. The actuator system of  claim 1 , further comprising:
 a communications bus connected to the auxiliary switch; and 
 a controller connected to the communications bus; and 
 wherein:
 the controller is remote from the auxiliary switch; 
 the make-connection position and the break-connection position of the auxiliary switch, relative to the rotation position of the shaft, are entered at the controller; and 
 the make-connection position and the break-connection position entered at the controller are sent as adjustment signals electronically via the communications bus to the auxiliary switch. 
 
 
     
     
       3. The actuator system of  claim 2 , wherein the communications bus is a two-wire polarity-insensitive system that conveys signals and power. 
     
     
       4. The actuator system of  claim 2 , wherein the make-connection position and the break-connection position of the auxiliary switch are automatically adjusted by the controller according to one or more variables. 
     
     
       5. The actuator system of  claim 4 , wherein a variable is temperature. 
     
     
       6. The actuator system of  claim 2 , wherein the make-connection position and the break-connection position of the auxiliary switch are adjusted in real time as the make-connection position and the break-connection position are entered at the controller. 
     
     
       7. A method for adjusting an auxiliary switch of an actuator for a heating, ventilating and air conditioning (HVAC) system, comprising:
 providing an auxiliary switch having adjustable make and break connection setpoints relative to one or more rotation positions of an HVAC actuator shaft; 
 adjusting the make and break connection setpoints, relative to the one or more rotation positions of the actuator shaft, with electronic signals; and 
 entering the make and break connection setpoints into a computer connected to the auxiliary switch. 
 
     
     
       8. The method of  claim 7 , wherein the computer is remotely connected to the auxiliary switch via a communications bus. 
     
     
       9. The method of  claim 8 , further comprising:
 rotating the actuation shaft with a motor; and 
 controlling the motor with the computer via the communications bus. 
 
     
     
       10. The method of  claim 9 , wherein the communications bus comprises just two polarity-insensitive wires. 
     
     
       11. The method of  claim 10 , wherein:
 the motor is controlled by one or more variables entered into the computer; and 
 the one or more variables are provided by one or more sensors. 
 
     
     
       12. The method of  claim 7 , wherein:
 the make and break connection setpoints are adjusted according to one or more variables entered into the computer; and 
 the one or more variables are provided by one or more sensors. 
 
     
     
       13. An actuator system for a heating, ventilating and air conditioning (HVAC) system, comprising;
 an HVAC actuator; 
 a control circuit connected to the actuator; 
 a processor connected to the control circuit; and 
 an auxiliary switch connected to the processor; and 
 wherein:
 the actuator has an actuator position; 
 the processor is connected to a communications bus, and the communications bus is connected to a controller remote from the auxiliary switch; and 
 a setpoint of the auxiliary switch is adjustable relative to the actuator position and is remotely adjustable at the controller. 
 
 
     
     
       14. The system of  claim 13 , wherein the setpoint of the auxiliary switch is adjustable via the communications bus and the processor in real time. 
     
     
       15. The system of  claim 13 , wherein the communications bus is a two-wire polarity-insensitive system. 
     
     
       16. The system of  claim 13 , further comprising an auxiliary potentiometer connected to the processor. 
     
     
       17. The system of  claim 16 , wherein the setpoint of the auxiliary switch is manually controlled by the auxiliary potentiometer. 
     
     
       18. The system of  claim 17 , wherein:
 if the actuator position is greater than a setpoint of the auxiliary switch set by the auxiliary potentiometer 
 THEN 
 activate the auxiliary switch 
 ELSE 
 de-activate the auxiliary switch. 
 
     
     
       19. The system of  claim 13 , wherein:
 the setpoint of the auxiliary switch is controlled by a command of the controller via the communications bus and the processor; and 
 if the actuator position is greater than the setpoint of the auxiliary switch set by the command of the controller 
 THEN 
 activate auxiliary switch 
 ELSE 
 de-activate auxiliary switch. 
 
     
     
       20. An actuator system for a heating, ventilating and air conditioning (HVAC) system, comprising;
 an HVAC actuator; 
 a control circuit connected to the actuator; 
 a processor connected to the control circuit; and 
 an auxiliary switch connected to the processor, wherein the auxiliary switch has a make-connection position and a break-connection position, 
 wherein the make-connection position and the break-connection position of the auxiliary switch are separately adjustable relative to one or more of:
 a temperature; or 
 a mode of the HVAC system 
 
 
     
     
       21. The system of  claim 16 , wherein the auxiliary potentiometer is accessible from both a first side and a second side of the actuator.